The present invention relates generally to means for electrically interconnecting printed circuit boards and, more particularly, to double ended contacts for electrically and mechanically interconnecting a stack of spaced printed circuit boards.
Stacking of printed circuit boards in electronic packaging is becoming more common in order to condense the size of the package. At the present time, it is common to utilize straight copper posts which extend through plated-through holes in stacked printed circuit boards for electrically interconnecting the printed circuitry on the boards. Sometimes metal spacers surrounding the rods are used for maintaining the boards in a predetermined spaced relationship. Reflow solder techniques are utilized to electrically connect the copper posts in the plated-through holes. One form of stacked printed circuit board assembly of the aforementioned type is disclosed in U.S. Pat. No. 2,913,634. Such assemblies have the disadvantage that in order to repair any board within the stack, all the copper posts must be removed from the stack of boards in order to remove the board which requires repair. This requires removal of all the solder joints between the copper posts and the printed circuit boards, which is time consuming and costly. Furthermore, precise board spacing is difficult to maintain, and tight manufacturing tolerances must be maintained in order to avoid misalignment of the plated-through holes in the boards which receive the copper posts.
U.S. Pat. No. 3,568,001 discloses another form of stacked printed board assembly utilizing elongated posts or contacts which extend through socket contacts mounted in the boards. The entire printed circuit board assembly must be disassembled in order to repair any one of the boards. Other stacked board assemblies are disclosed in U.S. Pat. Nos. 3,028,573; 3,205,469; 3,270,251; and 3,904,934. The stacked board assemblies disclosed in these patents require spacers in order to maintain the spacing between the boards, which adds to the complexity and cost of the assemblies.
It is the object of the present invention to provide an improved stacked printed board assembly in which the boards are easily separated for repair, and do not require separate spacers for maintaining the spacial relationship between the boards. Another object of the invention is to provide a novel double ended pin and socket contact for a stacked printed circuit board assembly which allows the boards to be electrically interconnected and mechanically spaced apart without maintaining tight manufacturing tolerances on the boards.